The present invention relates to an optical recording medium suitable when it is applied to an optical disc such as a compact disc, recording apparatus and method for the optical recording medium, and reproducing apparatus and method for the optical recording medium.
A compact disc (hereinafter, abbreviated to CD) has been spread as an optical disc. In the CD, audio data is sequentially divided into blocks, subjected to an encoding of an error correction code, and after that, and EFM (Eight To Fourteen) modulated, and a modulation result is recorded by an NRZI (Non Return to Zero Inverted) modulation.
As a result of the EFM modulation, for a basic period T serving as a period of a channel clock, the audio data is recorded onto the disc by a repetition of pits and a land having nine kinds of lengths 3T to 11T in which the basic period T is used as a unit. In case of a CD, each pit has a length of about 0.87 to 3.18 [xcexcm] in correspondence to 3T to 11T, a pit width of about 0.5 [xcexcm], and a depth of about 0.1 [xcexcm].
The audio data recorded on the CD is 2-channel data in which a sampling frequency is equal to 44.1 [kHz] and the number of quantization bits is equal to 16 bits. However, it is also demanded to realize a high sound quality and multichannels. In this case, it is necessary that there is reproducing compatibility in which the audio data can be reproduced by the existing CD player. It is not preferable that a time of an audio program which can be recorded on one CD becomes short due to the realization of the high sound quality and multichannels. Further, since a copy preventing technique for copyright protection is not used in the CD, in a present situation, data is illegally copied.
The invention is made in consideration of such a situation and it is an object of the invention to provide an optical recording medium in which a time of a program which can be recorded does not become short, there is a reproducing compatibility, a high sound quality can be realized, the copyright can be protected, and further, a use range of the optical medium such as a CD or the like can be extended. According to the invention, there are also provided recording apparatus and method for such an optical recording medium and reproducing apparatus and method for such an optical medium.
According to the invention of claim 1, there is provided an optical recording medium having tracks each of which is constructed by a plurality of pits which are formed on the basis of first data to be recorded and a land between the pits,
wherein the plurality of pits are deviated from the center of the track on the basis of second data.
According to the invention of claim 10, there is provided a recording apparatus for an optical recording medium, comprising:
a light source for outputting a recording laser beam;
a light modulator for modulating the recording laser beam outputted from the light source on the basis of supplied first data;
a light deflector for deflecting the modulated recording laser beam that is outputted from the light modulator on the basis of supplied second data in the direction which almost perpendicularly crosses a scanning direction of the modulated recording laser beam of an optical recording medium; and
an objective lens for converging the modulated recording laser beam that is outputted from the light deflector onto the optical recording medium.
According to the invention of claim 15, there is provided a reproducing apparatus for an optical recording medium having tracks each of which is constructed by a plurality of pits which are formed on the basis of first data to be recorded and a land between the pits, comprising:
an optical pickup for reading out the first data and second data from an optical recording medium on which the plurality of pits have been deviated from the center of the track on the basis of the second data;
a first demodulating unit for demodulating the first data on the optical recording medium on the basis of an output signal from the optical pickup; and
a second demodulating unit for demodulating the second data on the optical recording medium on the basis of the output signal from the optical pickup.
According to the invention of claim 22, there is provided a reproducing apparatus for an optical recording medium having tracks each of which is constructed by a plurality of pits which are formed on the basis of first data to be recorded and a land between the pits, comprising:
an optical pickup for reading out the first data and second data from an optical recording medium on which the plurality of pits have been deviated from the center of the track on the basis of the second data;
a first demodulating unit for demodulating the first data on the optical recording medium on the basis of an output signal from the optical pickup;
a second demodulating unit for demodulating the second data on the optical recording medium on the basis of the output signal from the optical pickup; and
a control unit for controlling the operation of the second demodulating unit on the basis of identification data read out from the optical recording medium by the optical pickup.
According to the invention of claim 32, there is provided an optical recording medium comprising:
a data recording region having a spiral track constructed by a plurality of pits which are formed on the basis of first data to be subjected to a predetermined modulation and recorded and a land between the pits; and
a management data region in which management data of the first data which is recorded in the data recording region is recorded,
wherein the plurality of pits are deviated from the center of the track on the basis of second data.
According to the invention of claim 44, there is provided a recording method for an optical recording medium, comprising the steps of:
modulating a recording laser beam outputted from a light source on the basis of supplied first data;
deflecting the modulated recording laser beam on the basis of supplied second data in the direction which almost perpendicularly crosses a scanning direction of the modulated recording laser beam of an optical recording medium; and
converging the modulated and deflected recording laser beam onto the optical recording medium by an objective lens.
According to the invention of claim 47, there is provided a reproducing method for an optical recording medium having tracks each of which is constructed by a plurality of pits which are formed on the basis of first data to be recorded and a land between the pits, comprising the steps of:
reading out first data and second data from an optical recording medium on which the plurality of pits have been deviated from the center of the track on the basis of the second data;
demodulating the first data on the basis of the data read out from the optical recording medium; and
demodulating the second data on the basis of the data read out from the optical recording medium.
According to the invention of claim 53, there is provided a reproducing method for an optical recording medium which has tracks each of which is constructed by a plurality of pits which are formed on the basis of first data to be recorded and a land between the pits and in which the plurality of pits are deviated from the center of the track on the basis of second data and on which identification data has been recorded, comprising the steps of:
demodulating the first data on the basis of the data read out from the optical recording medium; and
demodulating the second data on the basis of the data read out from the optical recording medium in accordance with an identification result of the identification data read out from the optical recording medium.